The present invention relates to an arrangement for control of a hydraulic motor, the two opposite faces of which to be impinged by pressure fluid are operatively connected with a first valve means for controlling the direction of movement of the motor, in which second valve means are connected in a hydraulic circuit with the first valve means for controlling the speed of the motor and in which further control means are provided which are actuated from a movable member of the motor to influence the change of the speed of the motor dependent on the position of the movable member.
In a known arrangement of this type for control of the advancing movement of a member of a machine tool, a separate block is provided for controlling the speed in which for two advancing movements of a reciprocating drive two fluid stream controllers, a four-way solenoid operated valve, as well as a roller actuated delay valve are provided. The roller actuation is necessary in order to assure a smooth deceleration of large masses between exactly determined end positions. The roller actuation requires, however, to space the block for control of the speed a certain distance from the block for control of the direction of the movable member of the tool machine, in which the two blocks have to be connected by conduits with each other. Such an arrangement requires therefore a relatively large space. In addition the adaptation of the arrangement for different load conditions is cumbersome.
It is also known to use in a control arrangement of the aforementioned kind an electrohydraulic servo valve and external electronic signal receivers. The disadvantage of this known arrangement is, however, that its operating safety is far from perfect and also that it is very expensive to produce.